How to Repair Broken Floor Tile

RON HAZELTON: Our first HouseCall today is a repair job in Tacoma Park, Maryland.  Matt and Sue Smith are having a problem with some ceramic floor tiles.

RON HAZELTON: Good Morning.  Hi guys.

SUE:  Good Morning, How are you?

RON HAZELTON: Hi Susan, How are ya?

SUE: Glad to meet you, Ron.

MATT:  Morning Ron.

RON HAZELTON:  Matt, pleasure to meet you.

SUE:  Hi, we have to go. 

RON HAZELTON:  You guys off to school?  Is it like this every morning here?

SUE:  It is, we have to go.  ----

RON HAZELTON:  Very busy, huh?

SUE:  --Sorry, we’re late!

RON HAZELTON:  O.K., guys, bye-bye!

MATT:  Have a good day, you guys!

RON HAZELTON:  Have a nice day!

KIDS:  Bye-bye!

RON HAZELTON: So, Matt, let’s take a look at the project.

MATT:  O.K., come on in.  We have a tile problem.  Over here in the corner.

RON HAZELTON:  Oh, yeah. 

RON HAZELTON:  When I see this many tiles coming loose from the floor, there are usually only a couple of explanations.  Either the mortar holding the tiles to the floor has failed, or the floor itself is moving or flexing.
RON HAZELTON:  Do you have any extra tile?

MATT: I do.  I have about 12 of these—

RON HAZELTON: Oh good.

MATT: --this size.  And I have these two pieces that, ah, came off.

RON HAZELTON: Since most of the loose tiles are in a high foot traffic area, I decide to first check the sub-floor, to see how thick it is.
RON HAZELTON:  O.K.  Ah, this is one possible explanation as to why this bond if failing.  Tile needs to have a thick subfloor underneath, at least one inch.  This plywood right here is only three-quarters of an inch.  The only way we’re going to know for sure is to cut a little piece of this away and get a look at the edge of this floor.

MATT:  O.K.

(SAWING SOUND)

RON HAZELTON: The news is not good. 
RON HAZELTON:  Ho, ho, ho, O.K., there you go.  Three-quarters of an inch.

JIM:  Three-quarters?

RON HAZELTON: Ceramic tile needs to have at least one inch of sub-flooring underneath it for proper support. 
RON HAZELTON:  Let me demonstrate what happens when the sub-floor underneath tile is too thin, and it’s flexing.  Let’s imagine that this is a piece of tile, right here, and this is the sub-floor.  As the sub-floor starts to, to ah, flex back and forth, like this, one of two things is going to happen.  Either the tile’s going to break, or it’s going to pop off, like that.  So…
RON HAZELTON:  The prescription for a permanent fit is time-consuming and costly.  In this case it would mean removing all the tiles in the room, adding one-quarter inch to the sub-floor, and then re-tiling.  That’s more than Matt wants to take on, at least right now.
RON HAZELTON:  … So do you want to go that far?

MATT: Well, I was thinking maybe we oughta just patch what we have, tear up the loose tiles, and just patch. 

RON HAZELTON: O.K., as long as you understand that this is gonna be a temporary fix.  You know, it probably will happen again.

MATT:  Mm, hmm, well, if it happens again, at least I’ll know how to fix it. 

RON HAZELTON:  O.K., true.
RON HAZELTON:  As we begin to take up the loose tiles, it becomes clear that there are a lot more than we first thought.  Some are so loose we can just lift them off with our hands.  I had hoped we could re-use many of the loose tiles, but most have a heavy coating of rock-hard mortar on the back, which is impossible to get off.  But fortunately, Matt’s supply of leftover tiles will bail us out.
RON HAZELTON: Now it’s time to start laying down the replacement tiles.  I’m gonna use a thin-set mortar.  This one has an acrylic, or latex additive that’ll help it bond better to the plywood.  So we’ve got some water in here… Matt, you got some more?

MATT:  Yup. 

RON HAZELTON: Pour about a gallon of water in here.  (WATER POURING)  This is our thin-set mortar, comes in powder form.  We’re gonna add that to the water.  And I’m gonna mix it up using this, uh paddle mixer and electric drill here.  (MIXING SOUND)

(MUSIC)

RON HAZELTON:  (MIXING SOUND)  Now as soon as we’ve finished mixing this, we’re gonna let it rest, or slake, as it’s called, for two or three minutes.  We’ll remix it very quickly and then we’ll use it.   This is a fast-setting mortar, we’ve only got about twenty minutes to use this. 
RON HAZELTON:  All right, this is just about the right consistency.  (PAUSE)  Uh, now, the two parts to the, to spreading this… uh, this is the trowel that we’re want to be using.  It’s a quarter-inch notch. 

MATT:  Mm-hmm.

RON HAZELTON:  We’re gonna start though by using the straight edge of the trowel first, and the idea here is hold this up (I’ll give you some there) on about a thirty-degree angle, and we wanna press this into contact (SCRAPING NOISE) with the surface down here, into all the crevices and depressions, so we get good contact.  This is all about getting it in firm contact, with the uh, in this case the plywood.  And then, once we’ve done that, turn the trowel over and use the notched edge, and that’s, this is where we’re gonna create furrows.  This gives us a uniform thickness.  So just one (PAUSE, SCRAPING) one pass down, like there.  That’s good.  
RON HAZELTON:  O.K., drop it in.

MATT:  Mm, hmm.

RON HAZELTON:  And once you get in contact just twist it like this a little bit. 

MATT:  O.K.

(MUSIC)

RON HAZELTON:  Soon it’s time to deal with the smaller shapes required to cover the face of the steps, and fill in around the edge of the room.  (SAWING)  We cut these to size using a water-cooled tile saw we rented locally.  To make sure the tiles are firmly in contact with the mortar, we tap them gently with a mallet, using a block of wood to distribute the force of the blow, and protect the face of the tile.  (TAP, TAP)

MATT:  What do you think?

RON HAZELTON: Looks good to me.  Let’s let it sit for about two hours, and then we can come back and do some grouting. 

MATT:  O.K.

RON HAZELTON: Now, normal thin-set mortar requires 24-hours dry time before you can do the grouting.  But this rapid-setting mortar that we used today is ready for grouting in just uh, two hours, so we can get started here.
First of all, you want to use the float to force the grout into this joint here.  All the way into the bottom.  Use a fair amount of pressure.  Then, tip the float up at about 45 degrees, and rake it across the face of the tile.  You notice that I’m going on a diagonal here?  From corner to corner?  The reason is that if I were to go this way, I’d come in and sort of scoop out too much uh, grout, right there on the joint.  So as long as I stay in a diagonal, that won’t happen. 

(MUSIC)

RON HAZELTON:  O.K. this is beginning to get a little firm, so uh, we can begin to start washing off some of the excess here. 
RON HAZELTON:  Using a damp sponge, we wipe off the excess grout from the face of the tiles, making sure we change the water frequently.  After three or four cleanings, we let a thin haze form on the surface.  Then buff it off with a clean, dry cloth.
RON HAZELTON:  Well, by golly, we did it!  And hopefully by using that acrylic-based, uh, thin-set, ah, you’ll get some good use out of this.  And if one does pop up, uh, can you handle it? 

MATT:  I think so, after everything you taught me.

RON HAZELTON: And thank goodness you had these extra tiles.  That’s something that you always wanna do when you put in a new tile floor, save some extra tiles.  Without those, I’m not sure we could have done this.  It was a pleasure working with you.

MATT:  Likewise, Ron.  Appreciate everything.

RON HAZELTON: Very welcome.